1. Field of the Invention
The present invention relates to AN IC element formed integrally with a coil on a chip, a method of manufacturing the IC element, an information carrier incorporating the IC element and a method of manufacturing the information carrier.
2. Description of Related Art
Heretofore, such a contactless type information carrier has been known which includes an IC element mounted internally of a substrate having a predetermined shape and an antenna coil electrically connected to the terminals of the IC element for effectuating in a noncontacting or contactless manner reception of electric power from a reader/writer and a signal transmission/reception with the reader/writer through the medium of the electromagnetic wave. As the information carriers of this species, there may be mentioned those referred to as the card-like information carriers, the coin-like information carriers, the button-like information carriers and the like named after the external appearance.
As the information carriers of the types mentioned above, the information carrier having an antenna coil patterned on a substrate or the information carrier having an antenna coil composed of a coil carried on a substrate has heretofore been employed. However, in recent years, there has been proposed an information carrier in which the IC element formed integrally with the antenna coil is mounted on the substrate and which features the capability of being manufactured inexpensively without need for the protection processing of the interconnection points between the antenna coil and the IC element and the moisture-proof treatment and additionally the excellent durability owing to insusceptibility to breakage of coil conductor regardless of stresses induced upon bending, torsion or the like of the substrate.
As a method of forming the antenna coil on the information carrier, a sputtering method is adopted. Thus, the electric conductor of the antenna coil formed integrally with the IC element is implemented in the form of an aluminum-sputtered film.
In this conjunction, it is however noted that when the antenna coil is formed integrally on the IC element, not only the winding diameter and the conductor width of the coil become smaller when compared with the case where the antenna coil composed of the winding is carried on the substrate, but also the number of turns of the coil is naturally limited, making it difficult to increase the range or distance for communication with the reader/writer or rendering it even impossible to ensure the communication range.
The present invention has been made with a view to disposing of the deficiencies of the hitherto known techniques such as mentioned above and hence it is contemplated with the present invention as a technical object to provide an information carrier incorporating an IC element formed integrally with an antenna coil and capable of ensuring an extended communication range or distance and a method of manufacturing the information carrier as well as a structure of the IC element formed integrally with the antenna coil and advantageously suited for employment in the information carrier of this sort and a method of manufacturing the IC element.